Pilot valve actuating mechanism for oil burners



May 22, 1928. Q 1,670,741

W. R. RAY

PILOT VALVE AGTUATING MECHANISM FOR OIL BURNERS Filed Jan. 2, 1924 s Sheets-$heet 1 WTOP/VEYS May 22, 1928. 1,670,741

- W. R. RAY

PILOT VALVE ACTUATING MECHANISM FOR OIL BURNERS Filed Jan. 1924 3, Sheets-Sheet 2 WILLIAM R. RAY.

May 22, 1928.

W. R. RAY V PILOT VALVE ACTUATING MECHANISM FOR OIL BURNERS,

Filed Jan. 1924 3 Sheets-Sheet 5 Patented May 22, 1928.

UNITED STATES WILLIAM RUTH BAY, 01E SAN FRANCISCO, CALIFORNIA.

PILOT-VALVE-AGTUATING MECHANISM FOR OIL BUR'NEBS'.

Application filed January 2, 1924. Serial No 688,894.

This invention relates to oil burners of the electric motor driven type, and especially to an automatically actuated gas pilot valve therefor, whereby the oil'discharging from the burner is ignited when the burner is started.

Where crude oil burners of the motordriven type are employed, and it is desired to manually or automatically start and stop the same from a distant point, for instance, by the closing of an electric switch, thermostatically or manually controlled, it is necessary to employ a gas pilot light or burner to ignite the oil burner when starting, and it is furthermore necessary to provide a pilot valve to regulate the flow of gas through the pilot light so as to give a momentary large flame to ignite the oil and a stand-by 0r pilot flame thereafter.

Pilot valves for the purpose just referred to are usually actuated by means of a solenoid or like magnet, and are by no means new, but they are nevertheless far from satisfactory in actual use. Certain types of solenoid-actuated valves, require a special switch to insure a momentary energization of the solenoid, thereby complicating the general arrangement and materially increasing the cost of installation. In other ty )es, the current remains on as long as the urner is in operation, thereby causing overheating and burning out of the solenoid magnet. In

others, the contact-breaking points are liable to. stick, again causing overheating and vburning outof the solenoid windings; in .fact, numerous other defects, mechanical and otherwise, could bementioned, but are hard ly thought necessary.

In the burner disclosed in the present ap. plication a single phase alternating current motor is used for the purpose of operating the oil burner. The stator of a motor of this type is usually provided with two sets of 'windings, one known as the main or running two to fiWE seconds, and as it is desirable to increase the size of the pilot flame at that time, I have found that it is possible to connect the solenoid magnet of a pilot valve in parallel with the starting winding and the centrifugal switch of the motor as a circuit thus obtained causes a momentary energization of the solenoid with a consequent increase in the size of the pilot flame at the proper time to insure ignition of the oil when the burner is started. This method of connecting the solenoid magnet of the pilot valve with the starting winding and the controlling switch of the motor entirely eliminates the difliculties and objections above mentioned; it simplifies the entire arrangement, and materially reduces the cost of installation. This method forms the subject matter of the present application and will be explained in moredetail by referring to the accompanying specification and drawings, in which Fig.- 1 is a front view of a hot .water or steam boiler showing the position of the burner with relation to the furnace, and also starting winding and the pilot valve are actuated.

Fig. 3 is an enlarged central, vertical section of the pilot valve.

Fig. 4 is a wiring diagram showing the circu ts controlled by the centrifugally actuated switch.

Referring to the drawings in detail. and particularly to Figs. 1 and 2, A indicates a standard form ofsteam or hot water boiler, and 2 the base thereof in which the furnace proper is located, B indicates the burner in general, C a fan or blower, and D an electric motor whereby the fan and the burner are operated.

The burner is of the rotary atomizing type and consists of a cup 3' secured on the outer end of a hollow or tubular shaft 4.

This shaft is supported in anti-friction bearings asindicated at 5, and it does not only I cup 3, but it also forms a support for a lower 6 and the rotor 7 of the motor D. The blower 6 is enclosed by a housing 8 and this housing form a support for the atomizing r is supported by hinges 9 formed on a front plate 10; this plate being attached to the furnace front or forming a part thereof.

The fan housing also forms a support for an air nozzle 11, which surrounds the atomizing cup, and it furthermore forms a support for the anti-friction bearings 5 and the motor housing D. This motor housing is provided with a jacket in which is formed an annular passage 12 and oil is circulated through this passage, as will hereinafter be described, first to cool the motor, and secondly to heat the oil before it is delivered to the atomizing cup 3.

The entire burner unit, to-wit, the fan housing, the bearing members 5, and the motor D, together with the air nozzle, as previously stated, is supported by the hinges 9 on the front plate 10 of the furnace box and as such may be readily swung to or from the furnace for inspection, repair or otherwise.

The furnace box may be constructed in any manner desired as this feature does not form any part of the present invention; in fact, the entire burner structure shown in this application is disclosed in several patents previously issued to me, (see for instance Patent N 0. 1,253,422, dated Jan. 15, 1918, and Patent No. 1,285,376, dated Nov. 19, 1918, and the only reason for illustrating the same is to clearly illustrate and describe the use andfunction of the pilot valve actuatingmechanism.

The burner installation shown in this instance is entirely automatic in operation. It is provided with means for maintaininga predetermined temperature in the room or rooms to be heated; the means employed being an adjustable thermostat such as indicated at 18. This thermostat is centrally located in the room to be heated and it is Connected with a thermostatic relay 19, which automatically controls the circuit through the motor. For instance, if it is desired to maintain a temperature of 72, it is only necessary to set the thermostat 18 at this temperature. The moment this temperature is reached, the relay 19 is automatically actuated and the circuit through -the motor is opened. Again, if the temperature drops below 72 F., the relay 19 is again automatically actuated and the circuit through the motor is closed. It is for this reason that means must be employed for automatically igniting the oil when the burner is started, and it is also necessary that means he provided for automatically opening and closing the oil flow to the atomizing cup when the burner is started or stopped.

The gas fed pilot burner employed is generally indicated at F. It serves the function of i niting the oil when the burner is started. he pilot burner is positioned directly below the atomizing cup 3 and as such is readily accessible. A small pilot flame is kept burning all the time and expands momentarily when the burner is started. To momentarily expand or increase the size of the pilot flame an automatic valve is employed. This valve is generally indicated at G in Fig. 1, but it is best illustrated in armature does not only serve the function of an armature, but it also serves the function of a valve as it normally closes the fiow of gas through the passages 21 and 22; it, however, opens communication between these passages when the magnet is energized as the reduced portion forming an annular passage 27 -will then register with the passages 21 and 22 and a free flow of gas through the valve will be permitted. A small flow of gas is maintained at all times to feed the pilot flame; this flow passing through a by-pass passage indicated by dotted lines at 28. The lower end of the armature terminates in a hollow piston 29, in which is mounted a check valve 30. This check valve opens downwardly, butis normally held against the seat by means of a spring 31. An oil chamber is formed above the piston 29, as indicated at 32, and is substantially filled with oil. The piston 29 divides the oil chamber 32 into the upper chamber shown and also into a lower chamber as indicated at 33. A by-pass passage indicated at 34 connects the upper and lower ends of the chamber and the flow of oil through this by-pass passage is regulated by a needle valve 35.

The operation of the pilot valve is briefly as follows: When the magnet 26 is momentarily energized, armature 25 is raised to an elevated position. The oil in the upper chamber 32 is by-passed through the valve 30 into the lower chamber during this movement and as the energization of the magnet is only momentary, the armature is soon released and is thus permitted to settle downwardly within the cylinder. This downward movement, when the armature is released, is slow as the valve 30 seats during downward movement and the speed with which the armature settles is dependent upon the transfer of the oil from the lower chamber to the upper chamber. The weight of the armature is such that the piston 29 will force the oil upwardly through the by-passpassage 34 and as the flow therethrough is controlled by the needle valve 35, it can readily be seen that a dash-pot action is secured, and fur-. ther that the settling speed of the armature may be regulated.

The time element thus obtained is sufficient to ignite the oil discharging from the burner as a large flame is discharged by the pilot burner as long as the annular passage 27 is registering with the passages 21 and .22. The moment, however, that the armature reaches the lower end of its stroke communication is closed and only a small quantity of gas will flow through the pilot burner as the only delivery will be through the bypass passage 28.

The general construction of the pilot valve just described is not particularly new, but merely illustrates one form of valve that is suitable for the purpose. The subject matter forming the invention of the present application relates to the method of energizing the solenoid magnet 26 and the mechanism employed. Having this particular feature in mind it might be well to state that the type of electric motor employed is a single phase alternating motor. The stator in a motor of this character is provided with two windings, (diagrammatically illustrated in Fig. 4), to-wit, a main or running winding such as indicated at 36, and a starting winding as indicated at 37. These windings are connected in parallel and the circuit through the starting winding is controlled by a centrifugally actuated switch, generally indicated at H in Fig. 2, and diagrammatically indicated at H in Fig. 4.

The circuit when closed through the motor enters through a wire 40 and passes through the main winding 36 and out through a Wire indicated at 41. The current also passes through the starting winding as this, together with the switch 8, is connected in parallel therewith, the parallel winding bein indicated by the wires 42 and 43.

he switch H, as previously stated, is centrifugally actuated, and if the motor is standing a circuit will be established through the contacts of the switch H. The moment,

however, a circuit is closed through the wires 40 and 41, the rotor starts. to rotate, and when a predetermined speed is reached switch H is opened centrifugally and the =circuit through the starting winding 1s broken.

- In actual practice it has been found that this being accomplished by connecting one terminal of the solenoid winding with one of the contacts of the switch as indicated at 45 by means of a wire f16, and by connecting the other terminal of the solenoid winding 47. It can therefore be seen that when a circuit is closed through the motor that a circuit will also be closed through the starting winding, the switch H and the solenoid mag.- net 26. The armature 25 will accordingly be elevated and a large flow of gas will enter the pilot bu'rner. The pilot burner thus produces a large flame when the burner is being started and the oil is sure to be ignited. The

moment the motor reaches a predetermined or decreased by changing the position of the,

needle valve 35.

By connecting the solenoid magnet in the manner here described, I obviate the necessity of installing specially constructed switches. Danger of overheating the solenoid windings or burning the same is also eliminated as the circuit maintained through the solenoid winding is seldom in excess of one-half a minute. Sticking of contacts,

etc., is also eliminated, and the cost of the equipment and the simplicity of the same are reduced and improved.

The present application is not concerned with the oil delivery to the burner or the method of controlling the same, but it might nevertheless be stated that the oil is supplied by a pipe which passes through a hollow pintle connecting the hinge members 9, and is finally directed to one side of the annular passage 12 formed in the motor housing as indicated at 51. It then passes through a jacket and out through a pipe 52. This pipe is connected with one end of a pipe 53, extending through the hollow or tubular motor shaft 4:, and the opposite end of the pipe 53 terminates in a goose-neck 54 positioned within the atomizing cup Mounted on the pipe 51 is an automatic valve 55. This valve is actuated by a solenoid magnet similar to that employed in connection with the pilot Valve. This mag-,

net is, however, connected in series with the motor and as such is energized when the motor circuit is closed, the only difl'erencc between the two solenoid magnets being that the solenoid controlling the valve 55 will retain the valve in an open-position as long as the circuit through motor is closed, and is will therefore not close the valve 55 except when the motor circuit is broken.

From the foregoing it can be seen that means are employed for automatically turn- .with the wire 41 through means of a wire ing on the oil when the motor is started, andthat the same means also automatically shuts oif the oil flow when the motor is stopped. Similarly, that means are employed for automatically igniting the oil when the motor is started; the two means specified being automatically or manually controlled from a distant point.

Having thus described my invention, what I claim and desire to secure by Letters Patent is-- 1. The combination with an electric motor driven liquid fuel burner and a gas pilot burner cooperating therewith, of a conduit through which gas is fed through the pilot burner, a valve in the conduit, an electromagnet for opening the valve, said magnet being connected in parallel with the motor circuit, whereby closing of the motor circuit will energize the magnet and open the valve, and means actuated by the motor whereby the circuit through the electro-magnet is automatically broken when the motor reaches a predetermined speed.

2. The combination with a burner of the character described and a single phase alternating current electric motor whereby it is operated, the stator of said motor including a. starting winding and a centrifugally actuated switch, of a solenoid magnet connected with the switch and the starting winding, a gas fed pilot light cooperating with the burner, and a pilot valve actuated by the solenoid magnet adapted to regulate the flow of gas to the pilot light.

driven oil burner of the character described,

of a gas fed pilot light cooperating with the burner, a valve regulating the flow of gas to the pilot light, an electro-magnct actuating the valve, means for closing an electric circuit through the motor and the electro-magnet, and means actuated by the motor whereby the circuit through the elec tro-niagnet is automatically broken when the motor reaches a predetermined speed.

5. The combination with an electric motor driven oil burner of the character described, of a gas fed pilot light cooperating with the burner, a valve regulating the flow of gas to the pilot light, an electro-magnet actuating the valve, means for closing an electric circuit through the motor and the elec tro-niagnet, a centrifugal governor operated by the motor, and a switch mounted in the circuit of the electro-magnet and adapted to be opened by the governor when the motor reaches a predetermined speeds WVILLIAM RUTH RAY. 

